1. Field of the Invention
The present invention relates to a connector coupling structure in which an elastic contact piece of a terminal is exposed from a terminal chamber in a state where the terminal is fit into the terminal chamber of a connector, and more particularly to a connector coupling structure between the elastic contact piece of the terminal and a printed board with a terminal connection strip corresponding to the elastic contact piece.
2. Description of the Prior Art
Conventionally, a first proposal of making connector coupling has been made by catching the above connector into an edge of a printed board. A second proposal of making connector coupling has been made by inserting the connector into an accommodating space of another connector. Such a connector coupling is formed mainly on a printed board attached to a switching unit provided on a meter or door trim panel of a motor vehicle.
The first proposal is disclosed in JP-A-37065. FIG. 13 is an exploded perspective view of a connector. FIGS. 14-16 are sectional views showing the process of coupling the connector at issue with another connector.
As shown in FIG. 13, a connector, generally 1, includes two flat-box shaped inner housings 4, each with a plurality of metal fittings 3 having elastic contact pieces 3a, respectively, within a box-shaped outer housing 2 with a rear face opened.
On each of the inner side walls of the outer housing 2, a pair of rotary shafts 5 are provided, and on each of the outer side walls of the inner housings 4, a pair of tube-like receivers 6 are formed. The shaft receiver 6 has a recess 6a on a side of inserting the inner housings 4 into the outer housing 2.
When the inner housings 4 are inserted into the outer housing 2, the recesses 6a are pushed in the rotary shafts 5. Each of spring members 7 is also hung over one of a pair of holding pieces opposite to each other on the inner walls of the outer housing 2 and spring receivers 9 formed on the outer side walls of the inner housings. Thus, the inner housings 4 are rotatably held within the outer housing 2 (see FIG. 14).
The spring members 7 urge the inner housings 4 so that the corresponding elastic contact pieces 3a of the terminals 3 become apart from each other. Thus, when the connector 1 starts to be coupled with the printed board of another connector, the elastic contact pieces 3a of the terminals 3 are brought into slight contact with the terminal connection strips formed on the printed board 10 (FIG. 15). As shown in FIG. 16, when the connector 1 is further pushed in another connector, introducing cams 12, formed on the inner upper and lower walls of a hood 11 surrounding the printed board 10, rotate the inner housings 4 towards the printed board 10 against the urging force of each of the spring members 7. At the same time, the elastic contact pieces 3a of the terminal connection pieces 10a (FIG. 13) slid while being pressed. Thus, coupling of the connector 1 with another connector is completed.
On the other hand, the above second proposal of making connector coupling is disclosed in Japanese Patent Publn. No. 6-65,092. FIG. 17 is an exploded perspective view of a connector a part of which is broken. FIG. 18 is a longitudinal sectional view of FIG. 17. FIG. 19 is an exploded perspective view of an exploded perspective view of a connector and another connector.
In FIGS. 17-19, reference numeral 13 denotes a connector, 14 a protection cover for opening/closing the exposed portion of a terminal of the connector 13, 15 another connector used for the above meter, switch unit, etc., and 16 a wire harness to be connected to each of terminals in the connector 13. In FIGS. 17-19, like reference numerals refer to like elements in FIGS. 13-16.
Within a connector housing 17 of the connector 13, a plurality of terminal chambers 18 are arranged in parallel. With the terminal 3 inserted into the terminal chamber 18, its elastic contact piece 3a is exposed from an opening portion 18a of the terminal chamber 18. In the vicinity of the terminal chambers 18, spaces 19 for detection are formed between the terminal chambers 18 and the a bottom plate 20, respectively. The terminal chamber 18 has a recess 18c at its bottom wall, which communicates with the space 19 for detection. At the recess 18c, a flexible engagement piece 21 is extended from the peripheral wall 18d of the terminal chamber 18. The flexible engagement piece 21 has an engagement tip 21a.
On both side walls 22 (only one is shown) of the connector housing 17, a groove 22a for sliding the protection cover 14 is formed. The side wall 22 has an engagement protrusion 22b in the vicinity of the inlet of the groove 22a. The side wall 22 has a slit 22c formed in its longitudinal direction. Further, within the connector housing 17, a passage 23 is formed which crosses substantially perpendicularly to the face where the protection cover 14 is opened/closed and communicates with the space 19 for detection. In the vicinity of the inlet of the passage 23, an engagement protrusion 23a is protruded from the connector housing 17.
The protection cover 14 includes a cover body 14a and a detection member 14b which are coupled with each other through a coupling member 14c. The protection cover 14 is attached to the connector housing 17 in such a fashion that both ends of the cover body 14a are inserted into the grooves 22a, the detection member 14b is inserted into the space 19, and the coupling member 14c is inserted into the communicating passage 23.
The other connector 15 includes a space 24 for accommodating the connector 13 and a printed board 10 affixed on the upper face. The printed board 10 is to be brought into contact with the elastic contact pieces 3a of the terminals 3 along the space 24. A protrusion 24a is provided uprightly on the bottom of the space 24 in a direction of fitting the connector 13 in the space. The protrusion 24a is to be brought into contact with the detecting member 14b of the protecting cover 14.
When the fitting terminal of the connector 13 is inserted in the accommodating space 24 of the other connector 15, while the protrusion 24a is pressed against the detecting member 14b, the coupling member 14c travels in the communicating passage 23. Thus, the protection cover 14 moves in an opening direction to open the exposed face of the elastic contact piece 3a of the terminal 3. Then, the connector 13 is fit into the accommodating space 24 of the other connector 15 so that while the elastic contact pieces 3a slide, they are brought into contact with the terminal connection strips 10a formed on the printed board 10 to make electrical connection therebetween.
The prior arts described above has the following disadvantage. Since the elastic contact pieces 3a of the terminals 3 are brought into electric contact with the terminal connection strips 10a in a sliding manner, the force required for connector coupling cannot be reduced so greatly so that the workability remains poor. Some manners of connector coupling may generate deformation or damage of the elastic contact pieces 3a and the terminal connection strips 10a.